Generally, a tire is formed from a plurality of tire constructing members. As shown in, for example, FIG. 8, respective parts such as an inner liner 2, a tread 3, side walls 4, and rim strips 5 are formed from rubber members, which are conformed to characteristics as demanded, and the rubber members are combined with tire reinforcement members, which contain cords such as a carcass layer 6 and a belt layer 7 to constitute a tire T. The reference numeral 8 in the figure denotes a bead portion including bead cores 9.
Conventionally, in order to build the respective rubber members, intended rubber members are obtained by performing extrusion through dies conformed to cross sectional shapes of the respective rubber members and then performing cut to predetermined length. A tire is built by sequentially sticking the rubber members on a building drum. For example, an inner liner, a lengthy sheet having a predetermined width is cut to predetermined length to be wound around a cylindrical-shaped building drum and the both ends of the sheet thus cut are joined in one location in a circumferential direction.
In recent years, in terms of conformability of a tire to multi-product small lot production, assembly accuracy, improvement in productivity, etc., as shown in, for example, JP-A-2002-178415, JP-A-2004-358738, JP-A-2004-216603, and JP-A-2004-216726, respective rubber members such as an inner liner are formed into predetermined cross sectional shapes by winding an unvulcanized rubber strip, which is extrusion-formed in a ribbon configuration, round cylindrical-shaped rotary support body, such as a building drum, spirally in a tire circumferential direction while overlapping a part of the rubber strip.
When the rubber strips are spirally wound and built, in order to push the rubber strips, which are continuously supplied, against a peripheral surface of the rotary support body to bond the rubber strips and air to escape between the rubber strips, a holding roll is ordinarily used simultaneously with winding of the rubber strips to sequentially press the rubber strips to stick the same (for example, JP-A-2004-216603 and JP-A-2004-216726).
At this time, as shown in FIG. 6, rubber strips R as wound with partial overlapping are susceptible to variation in a laminated posture 1R at a first circumference of winding and in a laminated posture 2R at a second circumference of winding. Laminated postures at subsequent circumferences (on and after a third circumference) are the same as that described above such that postures are varied according to feed pitches of rubber strips R and cross sectional shapes of rubber strips R, and fore portions in an advancing direction of traverse movement become concave. For rubber strips R, which are varied in posture, a simply cylindrical-shaped holding roll 130 in parallel to a peripheral surface of a rotary support body 110 shown in FIG. 7 is difficult to exert a pressing force on the whole width of the rubber strips R and so there is a fear that a pressing force on fore, concave portions in the advancing direction (arrow B) is short to lead to insufficient pressing and remaining voids. Also, depending upon patterns of winding, in the case in which a wind beginning position in winding of plural layers such as two layers is at positions other than edges of a rubber member of a building object, variation in a strip posture in the vicinity of wind beginning is further increased in addition to variation caused by steps due to the thickness of the rubber strips in the states described above, so that shortage in pressing force is brought about.
In, for example, JP-A-2004-216603, in addition to an applicator roll including a holding roll and serving to supply rubber strips to a rotary support body to spirally wind the same for sticking, a stitching roll is provided in a region just after sticking by the applicator roll to press and bond edge portions, which form steps due to overlapping of the rubber strips, against the rotary support body and squeeze steps formed in the edge portions, and the stitching roll squeezes the edge portions to eliminate the steps.
With the proposal described above, the stitching roll is fundamentally provided to position so that a width center thereof can become substantially the same as that of the applicator roll with a view to squeezing those steps at the edge portions caused by spiral winding with the rubber strips partially overlapping, that is, steps at rearward edge portions in the advancing direction of traverse movement, so that fore, concave portions in the advancing direction of traverse movement are not locally pressed for variation in laminated posture caused by spiral winding with partial overlapping. Therefore, there is a fear that fore portions in the advancing direction of traverse movement are not pressed sufficiently and voids are produced. That is, pressing intended for squeezing voids generated between rubber strips in view of variation in laminated postures in the advancing direction of traverse movement of the rubber strips is difficult.    Patent Document 1: JP-A-2002-178415    Patent Document 2: JP-A-2004-358738    Patent Document 3: JP-A-2004-216603    Patent Document 4: JP-A-2004-216726